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<td ><a href="../qtdoc/index.html">Qt 5.12</a></td><td ><a href="qtqml-index.html">Qt QML</a></td><td ><a href="qtqml-module.html">C++ 类</a></td><td >QQmlImageProviderBase</td></tr></table><table class="buildversion"><tr>
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<li class="level1"><a href="#public-types">公共类型</a></li>
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<li class="level1"><a href="#details">详细描述</a></li>
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<h1 class="title">QQmlImageProviderBase类</h1>
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<p><a href="qqmlimageproviderbase.html">QQmlImageProviderBase</a>类用于在QML引擎中注册图像提供程序。<a href="#details">更多…</a></p>
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<tr><td class="memItemLeft rightAlign topAlign"> 头文件：</td><td class="memItemRight bottomAlign">   <span class="preprocessor">#include &lt;QQmlImageProviderBase&gt;</span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += qml</td></tr></table></div><ul>
<li><a href="qqmlimageproviderbase-members.html">所有成员的列表，包括继承的成员</a></li>
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<h2 id="public-types">公共类型</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qqmlimageproviderbase.html#Flag-enum">Flag</a></b> { ForceAsynchronousImageLoading }</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> flags </td><td class="memItemRight bottomAlign"><b><a href="qqmlimageproviderbase.html#Flag-enum">Flags</a></b></td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> enum </td><td class="memItemRight bottomAlign"><b><a href="qqmlimageproviderbase.html#ImageType-enum">ImageType</a></b> { Image, Pixmap, Texture, ImageResponse }</td></tr>
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<h2 id="public-functions">公共函数</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> virtual QQmlImageProviderBase::Flags </td><td class="memItemRight bottomAlign"><b><a href="qqmlimageproviderbase.html#flags">flags</a></b>() const = 0</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QQmlImageProviderBase::ImageType </td><td class="memItemRight bottomAlign"><b><a href="qqmlimageproviderbase.html#imageType">imageType</a></b>() const = 0</td></tr>
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<!-- $$$QQmlImageProviderBase-description -->
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<h2 id="details">详细描述</h2>
<p><a href="qqmlimageproviderbase.html">QQmlImageProviderBase</a>类用于在QML引擎中注册图像提供程序。</p>
<p>图像提供程序必须在QML引擎中注册。QML引擎所知道的关于图像提供者的唯一信息是它们提供的图像数据的类型。要使用图像提供程序来获取图像数据，必须将<a href="qqmlimageproviderbase.html">QQmlImageProviderBase</a>指针转换为<a href="../qtquick/qquickimageprovider.html">QQuickImageProvider</a> 指针。</p>
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<p><b>参见 </b><a href="../qtquick/qquickimageprovider.html">QQuickImageProvider</a> 和 <a href="../qtquick/qquicktexturefactory.html">QQuickTextureFactory</a>。</p>
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<div class="types">
<h2>成员类型文档</h2>
<!-- $$$Flag$$$ForceAsynchronousImageLoading -->
<h3 class="flags" id="Flag-enum"><a name="Flag-enum"></a>enum QQmlImageProviderBase::<span class="name">Flag</span><br/>flags QQmlImageProviderBase::<span class="name">Flags</span></h3>
<p>定义此图像提供程序的特定要求或特性。</p>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QQmlImageProviderBase::ForceAsynchronousImageLoading</code></td><td class="topAlign tblval"><code>0x01</code></td><td class="topAlign">Ensures that image requests to the provider are run in a separate thread, which allows the provider to spend as much time as needed on producing the image without blocking the main thread.</td></tr>
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<p>Flags类型是<a href="../qtcore/qflags.html">QFlags</a>&lt;Flag&gt;的类型定义。它存储一个或多个标志值的组合。</p>
<!-- @@@Flag -->
<!-- $$$ImageType$$$Image$$$Pixmap$$$Texture$$$Invalid$$$ImageResponse -->
<h3 class="fn" id="ImageType-enum"><a name="ImageType-enum"></a>enum QQmlImageProviderBase::<span class="name">ImageType</span></h3>
<p>定义此图像提供程序支持的图像类型。</p>
<div class="table"><table class="valuelist"><tr valign="top" class="odd"><th class="tblConst">Constant</th><th class="tblval">Value</th><th class="tbldscr">Description</th></tr>
<tr><td class="topAlign"><code>QQmlImageProviderBase::Image</code></td><td class="topAlign tblval"><code>0</code></td><td class="topAlign">The Image Provider provides <a href="../qtgui/qimage.html">QImage</a> images. The <a href="../qtquick/qquickimageprovider.html#requestImage">QQuickImageProvider::requestImage</a>() method will be called for all image requests.</td></tr>
<tr><td class="topAlign"><code>QQmlImageProviderBase::Pixmap</code></td><td class="topAlign tblval"><code>1</code></td><td class="topAlign">The Image Provider provides <a href="../qtgui/qpixmap.html">QPixmap</a> images. The <a href="../qtquick/qquickimageprovider.html#requestPixmap">QQuickImageProvider::requestPixmap</a>() method will be called for all image requests.</td></tr>
<tr><td class="topAlign"><code>QQmlImageProviderBase::Texture</code></td><td class="topAlign tblval"><code>2</code></td><td class="topAlign">The Image Provider provides <a href="../qtquick/qsgtextureprovider.html">QSGTextureProvider</a> based images. The <a href="../qtquick/qquickimageprovider.html#requestTexture">QQuickImageProvider::requestTexture</a>() method will be called for all image requests.</td></tr>
<tr><td class="topAlign"><code>QQmlImageProviderBase::ImageResponse</code></td><td class="topAlign tblval"><code>4</code></td><td class="topAlign">The Image provider provides <a href="../qtquick/qquicktexturefactory.html">QQuickTextureFactory</a> based images. Should only be used in <a href="../qtquick/qquickasyncimageprovider.html">QQuickAsyncImageProvider</a> or its subclasses. The <a href="../qtquick/qquickasyncimageprovider.html#requestImageResponse">QQuickAsyncImageProvider::requestImageResponse</a>() method will be called for all image requests. Since Qt 5.6</td></tr>
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<h2>成员函数文档</h2>
<!-- $$$flags[overload1]$$$flags -->
<h3 class="fn" id="flags"><a name="flags"></a><code>[pure virtual] </code><span class="type"><a href="qqmlimageproviderbase.html#Flag-enum">QQmlImageProviderBase::Flags</a></span> QQmlImageProviderBase::<span class="name">flags</span>() const</h3>
<p>实现此方法以返回此图像提供程序的属性。</p>
<!-- @@@flags -->
<!-- $$$imageType[overload1]$$$imageType -->
<h3 class="fn" id="imageType"><a name="imageType"></a><code>[pure virtual] </code><span class="type"><a href="qqmlimageproviderbase.html#ImageType-enum">QQmlImageProviderBase::ImageType</a></span> QQmlImageProviderBase::<span class="name">imageType</span>() const</h3>
<p>实现此方法以返回此图像提供程序支持的图像类型。</p>
<!-- @@@imageType -->
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